System for conveying objects from a nested stack of objects to a printer for printing

ABSTRACT

A printer includes a conveyor that feeds objects from a stack of nested objects to the printer. The conveyor includes a member having protuberances that extend from the member to hold the lips of objects in the stack except for the object closest to the printheads in the printer. A spindle mounted to a member is moved to be within an orifice of the object closest to the printheads to engage that object and pull it from the stack. The spindle rotates to facilitate the printing of the object. After the object is printed, it is released from the spindle and gravity directs the printed object along a ramp to an opening in the printer for collection.

TECHNICAL FIELD

This disclosure relates generally to a system for printing onthree-dimensional (3D) objects, and more particularly, to systems forprinting on objects removed from a nested stack of objects.

BACKGROUND

Commercial article printing typically occurs during the production ofthe article. For example, ball skins are printed with patterns or logosprior to the ball being completed and inflated. Consequently, anon-production establishment, such as a distribution site, whichcustomizes products, for example, in region in which potential productcustomers support multiple professional or collegiate teams, needs tokeep an inventory of products bearing the logos of various teamsfollowed in the area. Ordering the correct number of products for eachdifferent logo to maintain the inventory can be problematic.

One way to address these issues in non-production outlets would be tokeep unprinted versions of the products, and print the patterns or logoson them at the distribution site. Adapting known printing techniques,such as two-dimensional (2D) media printing technology, to apply imagecontent onto three-dimensional objects is difficult. The difficultiesare especially compounded when the objects are nested in a stackedarrangement for storage as is the case in plastic cups and the like. Oneobject at a time needs to be removed from the stacked configuration ofobjects for printing and the run of objects to be printed may be shortas a customer only needs two or four of the objects printed with somecustom pattern. Therefore, printing systems capable of being operated innon-production environments that can print nested 3D objects areunknown, but desirable.

SUMMARY

A new printing system is configured to print the surface of nestedthree-dimensional (3D) objects one object at a time. The printing systemincludes a plurality of printheads, each printhead in the plurality ofprintheads being configured to eject marking material, a conveyorconfigured to move a stack of nested objects toward the plurality ofprintheads, the conveyor including a member having a plurality ofprotuberances that extend from the member to engage a portion of eachobject in the stack of nested objects except the object closest to theplurality of printheads, a spindle configured for reciprocal movement,an actuator operatively connected to the spindle to enable the actuatorto move the spindle within an orifice of the object in the stack ofnested objects that is closest to the plurality of printheads to engagethe object and to move the object to a position opposite the pluralityof printheads, and a controller operatively connected to the pluralityof printheads, the conveyor, and the actuator. The controller isconfigured to operate the conveyor to move at least a portion of thestack of nested objects within the printing system, to operate theactuator to move the spindle within the orifice of the object in thestack of nested objects that is closest to the plurality of printheadsto engage the object, remove the object from the stack, and move theobject to a position opposite the plurality of printheads, and tooperate the plurality of printheads to eject marking material onto theobject on the spindle.

Another embodiment of the new printing system includes a plurality ofprintheads, each printhead in the plurality of printheads beingconfigured to eject marking material, a conveyor configured to move astack of nested objects toward the plurality of printheads, a spindleconfigured for reciprocal movement, an actuator operatively connected tothe spindle to enable the actuator to move the spindle within an orificeof the object in the stack of nested objects that is closest to theplurality of printheads to engage the object, an opening positionedbelow the conveyor, a member having a first end and a second end, thefirst end of the member is positioned at the opening and the second endis positioned to receive objects released from the spindle, and acontroller operatively connected to the plurality of printheads, theconveyor, and the actuator. The controller is configured to operate theconveyor to move at least a portion of the stack of nested objectswithin the printing system, to operate the actuator to move the spindlewithin the orifice of the object in the stack of nested objects that isclosest to the plurality of printheads to engage the object, remove theobject from the stack, and move the object to a position opposite theplurality of printheads, to operate the plurality of printheads to ejectmarking material onto the object, and to operate the actuator to releasethe object from the spindle in response to printing of the object beingcompleted to enable gravity to direct objects to the first end of themember and along a length of the member to the second end and throughthe opening.

A new method of printing the surface of nested three-dimensional (3D)objects one object at a time includes operating a conveyor with acontroller to position protuberances on a member within the conveyorbetween portions of adjacent objects in a stack of nested objects on theconveyor and to move at least a portion of the stack of nested objectswithin a printing system, operating an actuator with the controller tomove a spindle within an orifice of an object in the stack of nestedobjects that is closest to a plurality of printheads to engage theobject, remove the object from the stack, and move the object to aposition opposite the plurality of printheads, and operating theplurality of printheads with the controller to eject marking materialonto the object on the spindle.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of a printing system thatprints surfaces of nested 3D objects one object at a time are explainedin the following description, taken in connection with the accompanyingdrawings.

FIG. 1 illustrates an upright printing system to feed objects from anested stack of objects to the system for printing.

FIG. 2 is the printing system of FIG. 1 with the housing cover removedto expose the internal components that print and discharge the printedobjects.

FIG. 3 is a side perspective view of the conveyor that moves a stack ofnested objects within the printing system of FIG. 1 for printing.

FIG. 4 is a side view of the conveyor shown in FIG. 3 that illustratesthe interaction of the helical belt of the conveyor with the nestedobjects in a stack of nested objects.

DETAILED DESCRIPTION

For a general understanding of the present embodiments, reference ismade to the drawings. In the drawings, like reference numerals have beenused throughout to designate like elements.

FIG. 1 depicts a printing system 100 configured to retrieve an objectfrom a stack of nested objects 104, print the surface of the retrievedobject, and discharge the printed object into a nested stack 108. Theprinting system 100 includes a housing 112 in which a printer ispositioned as shown in FIG. 2 for the printing of objects. As depictedin the figure, the nested stack of objects is a stack of plastic cupsalthough the nested stack can be of any objects capable of being nestedtogether and that present an orifice at one end of the nested stack. Thenested stack 104 is positioned within a conveyor 116 for translationinto the housing 112. The details of the conveyor structure arepresented below.

The internal components of the printing system 100 are shown in moredetail in FIG. 2. A shuttle 120 is mounted on a support member 124 forreciprocating movement along the member. A fixed pitch screw member 128is operatively connected to the shuttle 120 and an actuator 122 so theactuator can bidirectionally rotate the screw member 128 to move theshuttle bidirectionally along the member 124. The shuttle 120 isoperatively connected to a rod 132 that terminates into a spindle 136.The rod 132 is hollow to provide a conduit that pneumatically connectsspindle 136 to a vacuum source 140. As the spindle 136 travels with theshuttle 120 toward the stack 104, the spindle enters an orifice of thefirst object in the nested stack of objects in stack 104. One or moreholes in the spindle 136 enables the vacuum source 140 to pull air fromwithin the orifice of the first object and mate the interior of theobject with the spindle 136.

When the actuator 122 is operated to reverse rotation of the screwmember 128, the shuttle 120 returns to its home position, whichpositions the object 140A opposite two arrays of printheads 144 and 148,one on each side of the object. Each array 144 and 148 has fourprintheads, although fewer or more printheads can be configured withineach array. The eight printheads in the two arrays 144 and 148 areoperatively connected to ink supplies 152A to 152H, respectively, soeach printhead is individually and independently supplied by only oneink supply in the system 100. Another container 154 is provided to aprinthead maintenance system in the printer for the collection of wasteink from purging operations of the printheads. An actuator 134operatively connected to the rod 132 rotates the rod so the spindle 136rotates with the object 140A. The controller 156 operates the printheadswithin the printhead arrays 144 and 148 to print text and graphics ontothe object 140A with up to eight different colors. After the object 140Ais printed, a UV lamp 168, which is positioned below the printheadarrays 144 and 148, is operated by the controller 156 to cure the inkprinted on the surface of the object 140A when one or more of theprintheads used to print the surface of the object 140A ejected UV inkonto the surface of the object. Once the curing process is completed,the controller disconnects the vacuum source 140 from the rod 132 andthe spindle 136 so the weight of the object dislodges the object fromthe spindle 136. In some embodiments, the position at which the spindlestops to position the object opposite the plurality of printheads isshort of a mechanical stop 158. Once the printing of the object iscompleted, the controller operates the actuator to continue moving theobject away from the stack so the edge of the object encounters the stopto push the object from the spindle as an alternative scheme forreleasing the object from the spindle.

The lower portion of the opening 160 through which the conveyor 116extends is located at one end of a ramp 164. The other end of the ramp164 is operatively connected to an actuator 166 to move the other end ofthe ramp 164 toward and away from the trailing end of the object 140Apositioned on the spindle 136. When an object is released from thespindle, gravity directs the object onto the ramp 164, which had itsother end raised by the controller 156 operating the actuator 166 duringthe curing process. The object slides along the ramp 164 through thelower portion of the opening 160 and is aligned with previously ejectedobjects by the guide 172. A tab 176 is mounted to the housing 112 tosupport the stack of discharged objects within the guide 172. When a runof objects for a particular text and graphics pattern has been printedand discharged, the stack can be removed from the guide 172 so a stackof objects can be printed with another pattern of text and graphics.

The conveyor 116 is shown in more detail in FIG. 3. The conveyor 116includes a tray 320 having a channel 324 with a floor 328. A supportbracket 304 is operatively connected to an endless belt 308 that isentrained about a pair of pulleys 312 so rotation of the pulleys movesthe support bracket 304 bidirectionally within the channel 324 of thetray 320. One of the pulleys 312 is operatively connected to an actuator332 for bidirectional rotational movement of the pulley. The supportbracket 304 includes a pair of prongs 336 that support the bottom of alast object in a nested stack of objects and a centering tab 340 thatfits within a well of the bottom of the last object in the stack. Acurved support member 344 accommodates the curvature of the exteriorsurface of the last object in the stack and the member 344 terminates ina tab 348 that is parallel with a longitudinal wall of the channel 324.A sensor 352 is located at the end of the conveyor 116 that ispositioned within the printing system 100. This sensor can be an opticalsensor, a magnetic sensor, or a mechanical sensor. The sensor 352 isconfigured to detect the presence of tab 348 and generate an electricalsignal indicative of tab 348 being opposite the sensor. The controller156 is operatively connected to the sensor 352 to receive the signalgenerated by the sensor when tab 348 is positioned at the sensor and, inresponse, the controller operates the actuator 332 to reverse therotational direction of the pulley 312 to return the bracket 304 to theother pulley 312 so another stack of objects can be loaded into theconveyor 116 against the bracket 304.

FIG. 4 shows the interaction between the objects in the nested stack ofobjects 104 and the endless belt 308. Endless belt 308 includes anendless cable or wire 404 helically wrapped with a wire 408 at a fixedpitch along the entire length of the wire 404. The helically wrappedwire 408 is only shown at one end of the wire 404 to facilitate thefigure. The portions of the wire 408 that are positioned between lips412 of the objects help hold the objects in the stack. When the object140B at the end of the stack reaches the end of the conveyor where thespindle can contact the orifice in the object, the wire 408 follows thewire 404 and falls away from the lip of the object 140B within theprinting system 100. Thus, no portion of the wire 408 hinders the mostforward object 140B in the tray 324 from being removed from the stack104. When the spindle 136 (FIG. 2) enters the orifice of the object 140Band the vacuum flowing through the opening in the spindle pulls theinterior of the object into engagement with the spindle, the reversemovement of the shuttle 120 and the spindle 136 removes the object 140Bfrom the stack. The helically wound wire 408, however, provides enoughresistance to translation of the remaining objects in the stack thatthey remain in the conveyor 116 until the actuator 332 advances thepulley 312 enough that the wire 408 no longer engages the lip of themost forward object so that object can be removed once the objectcurrently printed has been ejected.

It will be appreciated that variations of the above-disclosed apparatusand other features, and functions, or alternatives thereof, may bedesirably combined into many other different systems or applications.Various presently unforeseen or unanticipated alternatives,modifications, variations, or improvements therein may be subsequentlymade by those skilled in the art, which are also intended to beencompassed by the following claims.

1. A printing system comprising: a plurality of printheads, eachprinthead in the plurality of printheads being configured to ejectmarking material; a conveyor configured to move a stack of nestedobjects toward the plurality of printheads, the conveyor including amember having a plurality of protuberances that extend from the memberto engage a portion of each object in the stack of nested objects exceptthe object closest to the plurality of printheads; a spindle configuredfor reciprocal movement; an actuator operatively connected to thespindle to enable the actuator to move the spindle within an orifice ofthe object in the stack of nested objects that is closest to theplurality of printheads to engage the object and to move the object to aposition opposite the plurality of printheads; and a controlleroperatively connected to the plurality of printheads, the conveyor, andthe actuator, the controller being configured to operate the conveyor tomove at least a portion of the stack of nested objects within theprinting system, to operate the actuator to move the spindle within theorifice of the object in the stack of nested objects that is closest tothe plurality of printheads to engage the object, remove the object fromthe stack, and move the object to a position opposite the plurality ofprintheads, and to operate the plurality of printheads to eject markingmaterial onto the object on the spindle.
 2. The printing system of claim1 wherein the actuator is further configured to rotate the spindle andthe object on the spindle as the controller operates the plurality ofprintheads to eject marking material on the object.
 3. The printingsystem of claim 1 wherein the member of the conveyor is an endless wireentrained about a pair of pulleys within the conveyor; and the memberfurther comprises: a second wire helically wrapped around a length ofthe endless wire at a fixed pitch to form the protuberances.
 4. Theprinting system of claim 3 further comprising: another actuatoroperatively connected to one of the pulleys to move the endless wireabout the pulleys.
 5. The printing system of claim 4, the conveyorfurther comprising: a bracket mounted to the endless wire to enable thebracket to move between the pulleys and move the stack of nestedobjects.
 6. The printing system of claim 5, the conveyor furthercomprising: a sensor mounted at one end of the conveyor that is closestto the plurality of printheads, the sensor being configured to generatean electrical signal in response to the bracket being opposite thesensor; and the controller is further configured to reverse operation ofthe other actuator to move the bracket to the pulley most distant fromthe plurality of printheads.
 7. The printing system of claim 6 whereinthe sensor is a mechanical sensor, an optical sensor, or a magneticsensor.
 8. The printing system of claim 6 further comprising: an openingpositioned below the conveyor; and a member having a first end and asecond end, the first end of the member is positioned at the opening andthe second end is positioned to receive objects released from thespindle to enable gravity to direct the objects to the first end of themember and through the opening.
 9. The printing system of claim 8further comprising: an actuator operatively connected to the second endof the member to move the second end of the member toward and away fromthe spindle.
 10. The printing system of claim 9 further comprising: avacuum source that is operatively connected to an opening in thespindle; and the controller is operatively connected to the vacuumsource, the controller being further configured to operate the vacuumsource in response to the spindle being within the orifice of the objectclosest to the plurality of printheads and to deactivate the vacuumsource in response to printing of an object by the plurality ofprintheads being completed.
 11. A method of printing directly ontoobjects comprising: operating a conveyor with a controller to positionprotuberances on a member within the conveyor between portions ofadjacent objects in a stack of nested objects on the conveyor and tomove at least a portion of the stack of nested objects within a printingsystem; operating an actuator with the controller to move a spindlewithin an orifice of an object in the stack of nested objects that isclosest to a plurality of printheads to engage the object, remove theobject from the stack, and move the object to a position opposite theplurality of printheads; and operating the plurality of printheads withthe controller to eject marking material onto the object on the spindle.12. The method of claim 11 further comprising: operating the actuatorwith the controller to rotate the spindle and the object on the spindleas the controller operates the plurality of printheads to eject markingmaterial on the object.
 13. The method of claim 12, the operation of theconveyor further comprising: operating another actuator operativelyconnected to one pulley in a pair of pulleys within the conveyor to movean endless wire entrained about the pulleys, the protuberances beingformed by a second wire helically wrapped around a length of the endlesswire at a fixed pitch.
 14. The method of claim 13 further comprising:operating the other actuator to move a bracket mounted to the endlesswire to enable the bracket to move between the pulleys and move thestack of nested objects.
 15. The method of claim 14 further comprising:generating with a sensor mounted at one end of the conveyor that isclosest to the plurality of printheads an electrical signal in responseto the bracket being opposite the sensor; and operating the otheractuator with the controller to reverse rotation of the pulley to movethe bracket to the pulley most distant from the plurality of printheads.16. The method system of claim 15, the generation of the electricalsignal further comprising: generating the electrical signal with amechanical sensor, an optical sensor, or a magnetic sensor.
 17. Themethod of claim 16 further comprising: directing objects released fromthe spindle along a member having a first end and a second end, thefirst end of the member being positioned at an opening below theconveyor and the second end being positioned to receive objects releasedfrom the spindle to enable gravity to direct the objects from the secondend of the member to the first end of the member and through theopening.
 18. The method of claim 17 further comprising: operating anactuator operatively connected to the second end of the member with thecontroller to move the second end of the member toward and away from thespindle.
 19. The method of claim 18 further comprising: operating withthe controller a vacuum source operatively connected to an opening inthe spindle in response to the spindle being within the orifice of theobject closest to the plurality of printheads; and deactivating thevacuum source in response to printing of an object by the plurality ofprintheads being completed. 20-39. (canceled)